[Inhibitory effect and mechanism of bone marrow mesenchymal stem cells on inflammation in rats with multiple organ dysfunction syndrome].

Objective To observe the anti-inflammatory effect and mechanism of bone marrow mesenchymal stem cell (BMSC) on multiple organ dysfunction syndrome (MODS) rats. Methods SD rats were randomly divided into control group, model group and BMSC group, with 10 rats in each group. Rats in model group and BMSC group were intraperitoneally injected with 7 mg/kg lipopolysaccharide (LPS) to establish MODS models. Rat BMSCs were cultured in vitro, and the fourth generation cells were used for experiments. The rats in BMSC group were injected with 1×106 BMSCs through the tail vein, and the rats in control group and model group were injected with the same amount of normal saline through the tail vein. 72 hours after MODS model was established, blood oxygen partial pressure (PaO2) and arterial carbon dioxide partial pressure (PaCO2) were detected by blood gas analyzer. ELISA were used to detect the bilirubin (TB), albumin (ALB), serum creatinine (Scr), blood urea nitrogen (BUN), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and cyclic adenosine monophosphate (cAMP). HE staining was performed to observe pathological changes in lung, liver and kidney tissues. Western blot analysis was used to detect the protein expression of protein kinase A (PKA) and nuclear factor kappa-B p65 (NF-κB p65) in tissues of lung, liver and kidney. Results Compared with control group, PaO2 in model group and BMSC group significantly decreased, while the PaCO2 significantly increased. TB, Cr, BUN, TNF-α and IL-6 levels was found increased, and ALB and cAMP levels was found decreased, along with the decreased PKA protein expression levels in lung, liver and kidney tissues, and increased NF-κB p65 protein expression levels. Compared with model group, PaO2 in BMSC group increased significantly, while its PaCO2 decreased markedly. It's also detected decreased TB, Cr, BUN, TNF-α and IL-6 levels, increased ALB and cAMP levels, as well as increased PKA protein expression levels in lung, liver and kidney tissues, and decreased NF-κB p65 protein expression levels. Conclusion BMSCs can reduce the damaged organ function and inhibit the release of inflammatory factors in MODS rats. The mechanism may be related to the change of cAMP/PKA/NF-κB signaling pathway.